1. Field of the Invention
The present invention relates to means for lifting or supporting modular furniture of the type used in offices, to allow access to an office floor, e.g. for replacement of carpets or other flooring, including panels of raised flooring, without the need to remove the furniture from the office.
2. Prior Art
Modern offices are often provided with so-called "modular furniture", which comprises an arrangement of panels interconnected at angles to form office dividers, and which have so-called "hanging tracks" used to support desks, bookshelves, and other necessary office equipment. These hanging tracks are vertical metal strips, usually located at the edges of the panels, having a series of undercut slots from which special hangers, with suitable hooks, can be suspended. Generally, these hanging tracks are aligned with feet which support the panels, and which usually provide the only contact between the floor and the modular furniture.
The fact that quite a number of such panels, and their associated desks and shelves, are connected together makes it time consuming and costly to dismantle this furniture and remove it from an off ice to allow carpeting or other flooring to be replaced. Accordingly, apparatus has been designed and used which will allow the panels and associated furniture to be temporarily raised so that new flooring can be placed underneath. Apparatus of this kind is described, for example, in:
U.S. Pat. No. 5,261,643, issued Nov. 16, 1993 to Wurdack; PA1 U.S. Pat. No. 5,299,779, issued Apr. 5, 1994 to Collins; PA1 U.S. Pat. No. 5,385,335, issued Jan. 31, 1995 to Wurdack; PA1 U.S. Pat. No. 5,490,757, issued Feb. 13, 1996 to Stratman; PA1 U.S. Pat. No. 5,529,287, issued Jun. 25, 1996 to Pelosi, Jr. et al.; and PA1 U.S. Pat. No. 5,628,610, issued May 13, 1997 to Stratman et al. PA1 a lower portion having a support plate suitable for engaging the underside of a panel adjacent to a leg; and PA1 an upper, stabilizer portion spaced above said support plate and having an undercut hook suitable for engagement with one of the hanging tracks so as to positively locate the jig in relation to the panel.
Several of these patents use lifting jigs which have plates with a series of hooks for engaging the hanging tracks of the panels; for example the Wurdack patents, and those of Stratman and Pelosi et al. have this feature. Applicants have found that the arrangements shown in these patents tend to lack the desired stability, since they positively engage only a relatively short length of the hanging track, typically 2 to 5 inches of the hanging track. Another drawback of these arrangements is that in some makes of panel the hanging tracks may be dislocated if the panels and attached furniture are lifted in this way.
Another shortcoming of the patented arrangements is that it is difficult or impossible to place carpeting underneath the leg of a panel, since this is usually where the lifting device is positioned. Some installers simply accommodate the panel leg and/or the lifting device by cutting out a portion of the carpet or carpet tile, or slitting this around the leg. In the Wurdack '335 patent, there is apparatus, shown in FIGS. 7-9, which provides a lifting device having splayed apart legs which can be placed at opposite sides of a panel leg, and which might allow a relatively small carpet tile to be placed under the panel leg if two joints between tiles happened to be located between the splayed apart legs. However this does not meet the problem of covering a whole floor; since the legs of this lifting apparatus cannot be moved once the furniture is lifted, there are still likely to be areas not accessible for reflooring. Also, it is often be difficult to predict precisely where a carpet tile is to be situated, and the splayed legs allow no room for adjustment. It will be evident from the drawings that in order for the hook 40 to fit into apertures 11 it is considerably narrower than the shaft 14.
The present invention firstly provides apparatus for lifting or supporting modular furniture which is fixed in stable manner to panels, and which holds these panels more stably than prior art apparatus. Secondly, it provides apparatus which allows relatively large carpet tiles, for example 3 foot square tiles, to be positioned under a panel leg and in its vicinity, and allows for changing the relationship between the panel legs and the temporary supporting feet of the apparatus even after a panel has been lifted.